/*
 * Copyright (c) 2011-2012 Alexander Dubu
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * o  Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * o  Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * o  Neither the name Axil nor the names of its contributors may be used to
 *    endorse or promote products derived from this software without specific
 *    prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
package axil.framework.template;

import axil.api.Context;
import axil.api.Formatted;
import axil.api.Persona;
import axil.framework.format.SimpleFormatting;

import static axil.framework.Functions.str;


/**
 * Simple variable substitution. If the object implements the Formatted
 * interface, then the object is localized for the local and formatting rules
 * provided. Otherwise, the value is simply converted to a string.
 */
class SimpleVariable implements Instruction {
	private final String ident;


	SimpleVariable(String ident) {
		this.ident = ident;
	}


	/**
	 * Execute this template instruction, returning the resulting formatted
	 * text. The context given may not actually contain any required variables;
	 * this condition must not result in the the throwing of an exception.
	 */
	public String execute(Persona persona, Context values) {
		Object v = values.get(ident);
		if (v == null) {
			return "(? " + ident + " ?)";
		}
		if (v instanceof Formatted) {
			return ((Formatted)v).format(persona, SimpleFormatting.object);
		}
		return str(v);
	}
}
